This document discusses drilling fluids and their properties. It provides an overview of the principal functions of drilling fluids, which include subsurface pressure control, cuttings removal and transport, suspension of solid particles, sealing of permeable formations, stabilizing the wellbore, preventing formation damage, cooling and lubricating the bit, transmitting hydraulic horsepower to the bit, facilitating collection of formation data, partial support of the drill string and casing weights, controlling corrosion, and assisting in cementing and completion. It also discusses drilling fluid classifications, properties such as viscosity and rheology, and key components of drilling fluids.
The document discusses drilling fluids or mud, which are fluids circulated during drilling operations. There are several types of drilling fluids including water-based, oil-based, foam-based, and synthetic-based fluids. Drilling fluids serve various important functions including removing cuttings from the well, controlling formation pressure, maintaining wellbore stability, minimizing damage to the reservoir, and cooling and lubricating the drill bit. The appropriate type of drilling fluid depends on factors like the desired performance, environmental considerations, safety, cost, and availability. Water-based and oil/synthetic-based fluids are described in more detail. The document also outlines various properties and tests used to analyze the characteristics of drilling fluids.
Drilling fluids are absolutely essential during the drilling process and considered the primary well control.
Know more now about such a very important component of the drilling process.
This document discusses drilling fluids, including their types, functions, properties, and additives. It covers the main types of drilling fluids as water-based and oil-based, and their key functions such as removing cuttings from the wellbore, maintaining wellbore pressure and stability, lubricating and cooling the drill bit. The most common additives are described, including weighting materials to increase mud density, viscosifiers to suspend cuttings and materials, and other additives that control filtration, rheology, alkalinity and other properties. Selection of the appropriate drilling fluid depends on formation data and requirements for each well section.
This document discusses various water-based mud systems used in drilling operations. It describes the basic systems commonly used like lignosulfonate systems and calcium treated systems. More complex systems are used as conditions change with increasing well depth, temperature and pressure. Factors that influence the choice of mud system include the application, geology of the formation, make-up water quality, drilling parameters, potential drilling problems, and rig equipment limitations. The document provides details on specific mud systems like potassium chloride PHPA mud, silicate mud and their components and applications.
This document discusses drilling fluid systems and their functions. It describes the classification of drilling muds as water-based or oil-based. Water-based muds can be further broken down and include bentonite muds, polymer muds, and muds with additives like gypsum, lime, potassium/lime, and mixed metal hydroxide. Oil-based muds include invert emulsion and mineral/synthetic oil-based muds. Key functions of drilling fluids are cooling and lubricating the drill bit, carrying cuttings to the surface, controlling formation pressure, and maintaining wellbore stability. Common measurements of mud properties are also outlined.
1. The document discusses different types of stuck pipe that can occur while drilling, including differential pressure pipe sticking and mechanical pipe sticking.
2. Differential pressure pipe sticking occurs when part of the drillstring embeds in the mudcake on the formation wall. Mechanical pipe sticking can be caused by cuttings accumulation, borehole instability, or key seating.
3. Methods to prevent or mitigate stuck pipe include maintaining low fluid loss and drilled solids levels, using smooth mudcake systems, and rotating drillstring. Common techniques for freeing stuck pipe include reducing hydrostatic pressure, oil spotting, or increasing mud weight.
The document discusses drilling fluids or mud, which are fluids circulated during drilling operations. There are several types of drilling fluids including water-based, oil-based, foam-based, and synthetic-based fluids. Drilling fluids serve various important functions including removing cuttings from the well, controlling formation pressure, maintaining wellbore stability, minimizing damage to the reservoir, and cooling and lubricating the drill bit. The appropriate type of drilling fluid depends on factors like the desired performance, environmental considerations, safety, cost, and availability. Water-based and oil/synthetic-based fluids are described in more detail. The document also outlines various properties and tests used to analyze the characteristics of drilling fluids.
Drilling fluids are absolutely essential during the drilling process and considered the primary well control.
Know more now about such a very important component of the drilling process.
This document discusses drilling fluids, including their types, functions, properties, and additives. It covers the main types of drilling fluids as water-based and oil-based, and their key functions such as removing cuttings from the wellbore, maintaining wellbore pressure and stability, lubricating and cooling the drill bit. The most common additives are described, including weighting materials to increase mud density, viscosifiers to suspend cuttings and materials, and other additives that control filtration, rheology, alkalinity and other properties. Selection of the appropriate drilling fluid depends on formation data and requirements for each well section.
This document discusses various water-based mud systems used in drilling operations. It describes the basic systems commonly used like lignosulfonate systems and calcium treated systems. More complex systems are used as conditions change with increasing well depth, temperature and pressure. Factors that influence the choice of mud system include the application, geology of the formation, make-up water quality, drilling parameters, potential drilling problems, and rig equipment limitations. The document provides details on specific mud systems like potassium chloride PHPA mud, silicate mud and their components and applications.
This document discusses drilling fluid systems and their functions. It describes the classification of drilling muds as water-based or oil-based. Water-based muds can be further broken down and include bentonite muds, polymer muds, and muds with additives like gypsum, lime, potassium/lime, and mixed metal hydroxide. Oil-based muds include invert emulsion and mineral/synthetic oil-based muds. Key functions of drilling fluids are cooling and lubricating the drill bit, carrying cuttings to the surface, controlling formation pressure, and maintaining wellbore stability. Common measurements of mud properties are also outlined.
1. The document discusses different types of stuck pipe that can occur while drilling, including differential pressure pipe sticking and mechanical pipe sticking.
2. Differential pressure pipe sticking occurs when part of the drillstring embeds in the mudcake on the formation wall. Mechanical pipe sticking can be caused by cuttings accumulation, borehole instability, or key seating.
3. Methods to prevent or mitigate stuck pipe include maintaining low fluid loss and drilled solids levels, using smooth mudcake systems, and rotating drillstring. Common techniques for freeing stuck pipe include reducing hydrostatic pressure, oil spotting, or increasing mud weight.
Production tubing is installed in oil and gas wells to allow hydrocarbons to flow from the reservoir to the surface while protecting the casing from reservoir fluids. Tubing is specified based on its size, length, grade, and connection type. Common tubing sizes range from 2-3/8" to 4-1/2" in diameter. Tubing joints are typically 20-48 feet in length. Tubing grade depends on the application and is chosen based on strength, corrosion resistance, and availability. Connections can be either upset or non-upset threaded types.
This document provides information about drilling fluids used in oil and gas drilling operations. It discusses the key components and functions of drilling fluids, including bringing cuttings to the surface, controlling subsurface pressures, lubricating and cooling the drill bit. It also describes various types of drilling fluids like water-based muds, calcium muds, lignosulphonate muds, and KCl/polymer muds. The document discusses the role of clays and colloid chemistry in drilling fluids and outlines the properties and uses of different clay minerals.
This document discusses sustainable drilling fluid solutions. It begins with basic terminology used in drilling fluids like mud types, additives, and functions of mud. Water-based mud and oil-based mud are compared, noting that WBM is less toxic and can meet environmental issues but is not stable above 400°F, while OBM is stable above 400°F but more toxic. New developments in bio-polymers are discussed that can viscosify drilling fluids with less toxicity and better stability. In conclusion, water-based muds with bio-polymers are the most sustainable option while also addressing environmental concerns related to drilling fluids.
This document provides an overview of drilling fluids and their role in drilling operations. It discusses the components and properties of drilling fluids, including continuous and dispersed phases as well as additives. The types of drilling fluids are described, including water-based muds, oil-based muds, gases, and gas-liquid mixtures. The key functions of drilling fluids to support drilling operations are also outlined. The document concludes with discussions of pressure terminologies and examples of calculations related to drilling fluid properties and components.
Primary cementing involves placing cement between the casing and borehole to isolate zones and support the casing. It involves running casing, circulating mud, pressure testing, pumping wash/spacer, mixing and pumping cement slurry, and displacing with fluid. Secondary cementing, like squeeze cementing, is used to repair improper zonal isolation, eliminate water intrusion, or repair casing leaks by pumping cement through perforations or casing leaks. It can be done with low or high pressure placement using techniques like running squeeze or hesitation squeeze to fill perforations or fractures.
WELL COMPLETION, WELL INTERVENTION/ STIMULATION, AND WORKOVERAndi Anriansyah
This document discusses various well completion, intervention, and workover topics including:
- Well completion involves preparing the well for production by installing equipment like casing and tubing.
- Open hole and cased hole completions are described, along with advantages and disadvantages of each.
- Well intervention operations like scale removal, acidizing, and sand cleaning are performed during production.
- Formation damage from fluids introduced into the well is also discussed.
- Stimulation techniques like acidizing and hydraulic fracturing aim to increase well productivity. The document outlines the processes, equipment, and evaluation of these operations.
- Other topics covered include intelligent well completions, perforating, sand control, squeeze cement
Casing is essential for safely drilling oil and gas wells. It must withstand forces during drilling and through the life of the well. Different casing strings are run to isolate formations with different pressures and seal off problematic zones to allow deeper drilling. Surface casing isolates fresh water and supports blowout preventers. Intermediate casing increases pressure integrity to drill deeper and protects progress. Production casing houses completion equipment and isolates the producing zone. Liners are shorter strings hung from intermediate casing to complete zones economically. Proper casing and cementing is crucial to isolate formations and prevent communication between zones.
After drilling is completed, wells undergo completion procedures to prepare them for production. This involves setting production casing and cementing it through the target zone. Tubing is run inside the casing with a packer to isolate the production zone. A Christmas tree is installed to control flow. Completion types include open hole, liners, and perforated casing. Perforating creates holes through casing into the formation. Some formations require stimulation like acidizing to improve permeability or fracturing to create conductive fractures held open by proppant. This increases flow into the wellbore.
A drilling fluid, or mud, is circulated during drilling operations to carry cuttings to the surface, control formation pressure and maintain wellbore stability, cool and lubricate the drill bit, and minimize damage to the reservoir. There are three main types of drilling fluid: gaseous (like air), aqueous (water-based fluids containing additives like bentonite or polymers), and non-aqueous (oil- or synthetic-based). Proper handling and cleaning methods are required due to potential health and safety hazards from some drilling fluid components.
This document provides an overview of lost circulation, which occurs when drilling fluid is lost into porous or fractured formations. It discusses the types and severity of lost circulation, as well as methods for preventing, locating, and treating lost circulation zones. Key points include that lost circulation can lead to blowouts if not addressed, and that preventing excessive downhole pressure and identifying weak formations are important. Locating lost zones involves surveys to detect where fluid flows into formations, while treatments require sealing fractures or pores with lost circulation materials.
The document discusses cement used in oil and gas wells. It covers cement composition, classes of cement, additives for controlling density, acceleration, retardation and viscosity. It also discusses cementing operations, equipment and performing a good cementing job. Key factors include casing centralization, pipe movement, drilling fluid viscosity, hole condition and achieving proper displacement velocity.
This document discusses squeeze cementing techniques and considerations. Squeeze cementing involves pumping cement slurry under pressure against a permeable formation to create a cement seal. Key aspects covered include reasons for squeeze cementing, slurry design factors like viscosity and fluid loss control, laboratory testing methods, and primary concerns like establishing an injection rate and avoiding formation fracture. Detailed explanations are provided for methods like running squeezes through packers or cement retainers and different injection techniques.
The document discusses the functions and types of casing strings used in oil and gas wells. It describes the different casing strings like conductor casing, surface casing, intermediate casing, and production casing. It also covers casing design criteria like classifications based on outside diameter, length, connections, weight, and grade. The mechanical properties of casing are discussed in relation to withstanding tensile, burst, and collapse loads during drilling and production operations.
DRILLING FLUIDS FOR THE HPHT ENVIRONMENTMohan Doshi
A BRIEF REVIEW OF THE DRILLING FLUIDS FOR DRILLING HPHT WELLS. HPHT WELLS ARE NOT BUSINESS AS USUAL AND THE SAME APPLIES TO HPHT DRILLING FLUIDS. THE FLUID CHEMISTRY AND THE FLUID COMPOSITION HAVE TO BE TAILORED TO MEET THE RIGORS OF THE HIGH TEMPERATURE ENVIRONMENT
This document discusses the design of drillstrings and bottom hole assemblies (BHAs). It covers the components of drillstrings including drill pipe, drill collars, heavy weight drill pipe, and stabilizers. It also discusses BHA configurations and the purpose and components of BHAs. The document provides information on selecting drill collars and drill pipe grades. It covers criteria for drillstring design including collapse pressure, tension loading, and dogleg severity analysis.
The document discusses various properties of drilling fluids including density, cation exchange capacity, filtration properties, pH, rheology, alkalinity, lubricity, and corrosivity. It defines these key terms and describes methods for measuring properties such as cation exchange capacity, pH, rheology, and corrosivity. Controlling properties like pH and alkalinity is important for drilling fluid performance and stability.
This document provides an introduction to well control from Kingdom Drilling Services. It discusses primary and secondary well control, including maintaining pressure and monitoring flows. Loss of primary control can occur through pressure changes or lost circulation. Secondary control indicators include increased flow rates or mud pit volume changes. Methods for controlling kicks include circulating or bullheading. The document also covers well control terms, blowout prevention, shallow well hazards, and lost circulation detection and remedies.
This document provides an overview of a mud engineer trainee's work experience with two rigs, DQE-32 and DQE-51. It discusses the functions of drilling fluid, types of mud, testing procedures, chemical categories used in mud systems, calculations, cementing operations, formation and downhole problems, and general mud engineering information. The trainee thanks their mentors at Petrochem for providing training support over their 3-month internship.
The document discusses well completion and testing methods. It begins with welcoming 7th semester mining students and introducing the instructor. It then provides definitions and overview sections on well completion, well testing, and drill stem testing. The document describes different well completion methods like open hole, cased hole, liner, and tubing completions. It also discusses wellhead equipment, well testing operations, and considerations for high pressure and high temperature testing. Overall, the document provides information on various aspects of well completion and testing.
The document discusses drilling fluids, including their types, functions, properties, and additives. There are two main types of drilling fluids: water-based and oil-based. Drilling fluids must perform several key functions, such as controlling subsurface pressures, removing cuttings from the wellbore, lubricating the drill bit, and maintaining wellbore stability. Various additives are used to achieve the desired properties, including weighting agents, viscosifiers, filtration control agents, and lost circulation materials. The selection of drilling fluids requires consideration of formation and drilling conditions.
The document discusses drilling fluids, including their types, functions, properties, additives, and equipment/design considerations. The key types are water-based and oil-based muds. Drilling fluids must perform critical functions like controlling subsurface pressures, removing cuttings from the wellbore, lubricating the drill bit, and maintaining wellbore stability. Achieving these functions depends on optimizing properties like density, viscosity, and gel strength through the use of various additives like weighting agents, viscosifiers, and filtration control materials. Careful fluid selection and design is needed based on formation data and drilling conditions.
Production tubing is installed in oil and gas wells to allow hydrocarbons to flow from the reservoir to the surface while protecting the casing from reservoir fluids. Tubing is specified based on its size, length, grade, and connection type. Common tubing sizes range from 2-3/8" to 4-1/2" in diameter. Tubing joints are typically 20-48 feet in length. Tubing grade depends on the application and is chosen based on strength, corrosion resistance, and availability. Connections can be either upset or non-upset threaded types.
This document provides information about drilling fluids used in oil and gas drilling operations. It discusses the key components and functions of drilling fluids, including bringing cuttings to the surface, controlling subsurface pressures, lubricating and cooling the drill bit. It also describes various types of drilling fluids like water-based muds, calcium muds, lignosulphonate muds, and KCl/polymer muds. The document discusses the role of clays and colloid chemistry in drilling fluids and outlines the properties and uses of different clay minerals.
This document discusses sustainable drilling fluid solutions. It begins with basic terminology used in drilling fluids like mud types, additives, and functions of mud. Water-based mud and oil-based mud are compared, noting that WBM is less toxic and can meet environmental issues but is not stable above 400°F, while OBM is stable above 400°F but more toxic. New developments in bio-polymers are discussed that can viscosify drilling fluids with less toxicity and better stability. In conclusion, water-based muds with bio-polymers are the most sustainable option while also addressing environmental concerns related to drilling fluids.
This document provides an overview of drilling fluids and their role in drilling operations. It discusses the components and properties of drilling fluids, including continuous and dispersed phases as well as additives. The types of drilling fluids are described, including water-based muds, oil-based muds, gases, and gas-liquid mixtures. The key functions of drilling fluids to support drilling operations are also outlined. The document concludes with discussions of pressure terminologies and examples of calculations related to drilling fluid properties and components.
Primary cementing involves placing cement between the casing and borehole to isolate zones and support the casing. It involves running casing, circulating mud, pressure testing, pumping wash/spacer, mixing and pumping cement slurry, and displacing with fluid. Secondary cementing, like squeeze cementing, is used to repair improper zonal isolation, eliminate water intrusion, or repair casing leaks by pumping cement through perforations or casing leaks. It can be done with low or high pressure placement using techniques like running squeeze or hesitation squeeze to fill perforations or fractures.
WELL COMPLETION, WELL INTERVENTION/ STIMULATION, AND WORKOVERAndi Anriansyah
This document discusses various well completion, intervention, and workover topics including:
- Well completion involves preparing the well for production by installing equipment like casing and tubing.
- Open hole and cased hole completions are described, along with advantages and disadvantages of each.
- Well intervention operations like scale removal, acidizing, and sand cleaning are performed during production.
- Formation damage from fluids introduced into the well is also discussed.
- Stimulation techniques like acidizing and hydraulic fracturing aim to increase well productivity. The document outlines the processes, equipment, and evaluation of these operations.
- Other topics covered include intelligent well completions, perforating, sand control, squeeze cement
Casing is essential for safely drilling oil and gas wells. It must withstand forces during drilling and through the life of the well. Different casing strings are run to isolate formations with different pressures and seal off problematic zones to allow deeper drilling. Surface casing isolates fresh water and supports blowout preventers. Intermediate casing increases pressure integrity to drill deeper and protects progress. Production casing houses completion equipment and isolates the producing zone. Liners are shorter strings hung from intermediate casing to complete zones economically. Proper casing and cementing is crucial to isolate formations and prevent communication between zones.
After drilling is completed, wells undergo completion procedures to prepare them for production. This involves setting production casing and cementing it through the target zone. Tubing is run inside the casing with a packer to isolate the production zone. A Christmas tree is installed to control flow. Completion types include open hole, liners, and perforated casing. Perforating creates holes through casing into the formation. Some formations require stimulation like acidizing to improve permeability or fracturing to create conductive fractures held open by proppant. This increases flow into the wellbore.
A drilling fluid, or mud, is circulated during drilling operations to carry cuttings to the surface, control formation pressure and maintain wellbore stability, cool and lubricate the drill bit, and minimize damage to the reservoir. There are three main types of drilling fluid: gaseous (like air), aqueous (water-based fluids containing additives like bentonite or polymers), and non-aqueous (oil- or synthetic-based). Proper handling and cleaning methods are required due to potential health and safety hazards from some drilling fluid components.
This document provides an overview of lost circulation, which occurs when drilling fluid is lost into porous or fractured formations. It discusses the types and severity of lost circulation, as well as methods for preventing, locating, and treating lost circulation zones. Key points include that lost circulation can lead to blowouts if not addressed, and that preventing excessive downhole pressure and identifying weak formations are important. Locating lost zones involves surveys to detect where fluid flows into formations, while treatments require sealing fractures or pores with lost circulation materials.
The document discusses cement used in oil and gas wells. It covers cement composition, classes of cement, additives for controlling density, acceleration, retardation and viscosity. It also discusses cementing operations, equipment and performing a good cementing job. Key factors include casing centralization, pipe movement, drilling fluid viscosity, hole condition and achieving proper displacement velocity.
This document discusses squeeze cementing techniques and considerations. Squeeze cementing involves pumping cement slurry under pressure against a permeable formation to create a cement seal. Key aspects covered include reasons for squeeze cementing, slurry design factors like viscosity and fluid loss control, laboratory testing methods, and primary concerns like establishing an injection rate and avoiding formation fracture. Detailed explanations are provided for methods like running squeezes through packers or cement retainers and different injection techniques.
The document discusses the functions and types of casing strings used in oil and gas wells. It describes the different casing strings like conductor casing, surface casing, intermediate casing, and production casing. It also covers casing design criteria like classifications based on outside diameter, length, connections, weight, and grade. The mechanical properties of casing are discussed in relation to withstanding tensile, burst, and collapse loads during drilling and production operations.
DRILLING FLUIDS FOR THE HPHT ENVIRONMENTMohan Doshi
A BRIEF REVIEW OF THE DRILLING FLUIDS FOR DRILLING HPHT WELLS. HPHT WELLS ARE NOT BUSINESS AS USUAL AND THE SAME APPLIES TO HPHT DRILLING FLUIDS. THE FLUID CHEMISTRY AND THE FLUID COMPOSITION HAVE TO BE TAILORED TO MEET THE RIGORS OF THE HIGH TEMPERATURE ENVIRONMENT
This document discusses the design of drillstrings and bottom hole assemblies (BHAs). It covers the components of drillstrings including drill pipe, drill collars, heavy weight drill pipe, and stabilizers. It also discusses BHA configurations and the purpose and components of BHAs. The document provides information on selecting drill collars and drill pipe grades. It covers criteria for drillstring design including collapse pressure, tension loading, and dogleg severity analysis.
The document discusses various properties of drilling fluids including density, cation exchange capacity, filtration properties, pH, rheology, alkalinity, lubricity, and corrosivity. It defines these key terms and describes methods for measuring properties such as cation exchange capacity, pH, rheology, and corrosivity. Controlling properties like pH and alkalinity is important for drilling fluid performance and stability.
This document provides an introduction to well control from Kingdom Drilling Services. It discusses primary and secondary well control, including maintaining pressure and monitoring flows. Loss of primary control can occur through pressure changes or lost circulation. Secondary control indicators include increased flow rates or mud pit volume changes. Methods for controlling kicks include circulating or bullheading. The document also covers well control terms, blowout prevention, shallow well hazards, and lost circulation detection and remedies.
This document provides an overview of a mud engineer trainee's work experience with two rigs, DQE-32 and DQE-51. It discusses the functions of drilling fluid, types of mud, testing procedures, chemical categories used in mud systems, calculations, cementing operations, formation and downhole problems, and general mud engineering information. The trainee thanks their mentors at Petrochem for providing training support over their 3-month internship.
The document discusses well completion and testing methods. It begins with welcoming 7th semester mining students and introducing the instructor. It then provides definitions and overview sections on well completion, well testing, and drill stem testing. The document describes different well completion methods like open hole, cased hole, liner, and tubing completions. It also discusses wellhead equipment, well testing operations, and considerations for high pressure and high temperature testing. Overall, the document provides information on various aspects of well completion and testing.
The document discusses drilling fluids, including their types, functions, properties, and additives. There are two main types of drilling fluids: water-based and oil-based. Drilling fluids must perform several key functions, such as controlling subsurface pressures, removing cuttings from the wellbore, lubricating the drill bit, and maintaining wellbore stability. Various additives are used to achieve the desired properties, including weighting agents, viscosifiers, filtration control agents, and lost circulation materials. The selection of drilling fluids requires consideration of formation and drilling conditions.
The document discusses drilling fluids, including their types, functions, properties, additives, and equipment/design considerations. The key types are water-based and oil-based muds. Drilling fluids must perform critical functions like controlling subsurface pressures, removing cuttings from the wellbore, lubricating the drill bit, and maintaining wellbore stability. Achieving these functions depends on optimizing properties like density, viscosity, and gel strength through the use of various additives like weighting agents, viscosifiers, and filtration control materials. Careful fluid selection and design is needed based on formation data and drilling conditions.
This document provides an overview of a course on drilling fluids technology. It discusses the key functions of drilling fluids, including hole cleaning by transporting cuttings, pressure control by balancing subsurface pressures, suspending solids to prevent settling, minimizing formation damage, isolating fluids from the formation through filter cakes, providing cooling and lubrication, and powering downhole tools. It covers topics like mud properties and measurements, mud rheology, types of muds, hydraulics, pressure calculations, and containment. The first chapter focuses on the functions of drilling fluids in more depth.
This document provides an overview of drilling fluids. It discusses the key functions of drilling fluids, including transporting cuttings to the surface, cleaning the drill bit, providing hydrostatic pressure, preventing fluid loss, and lubricating and cooling the drill string. It also describes common drilling fluid types like water-based and oil-based muds. Important drilling fluid properties are defined, such as density, viscosity, gel strength, and fluid loss. Common drilling fluid additives and their purposes are explained. Hazards that can be addressed by proper fluid selection and properties management are also outlined.
Determination of Effect Bentonite and Additives On Drilling FluidsIRJESJOURNAL
Abstract :- Drilling fluids Play a vital role in hole Cleaning suspension of cuttings, prevent caving, and ensure the tightness of the well wall. Moreover they also help in cooling and lubricating the drilling tool, transfer the hydraulic power and carry information about the nature of the drilled formation by raising the cuttings from the bottom to the surface, using a simple mixture of water and clays, to complex mixtures of various specific organic and inorganic products as additives. These additives improve fluid rheological properties and filtration capability, allowing bits to penetrate heterogeneous geological formations The mud used in this work is barite and bentonites at different samples to know the difference in their specific gravity, viscosity, surface tension, and pH of the samples when chemical additives are added.
Determining the Sand Content in Various Compositions of Drilling MudIRJESJOURNAL
Abstract :- Drilling is an important part of the oil industry and penetration rate must be enhanced to ensure speedy completion of drilling operation. Weight on bit, Rotary speed, drill bit type, formation characteristics and mud properties are the basic factors that affect the penetration rate of a bit. Regular determination of the sand content of drilling mud is necessary because these particles can be highly abrasive, and can cause excessive wear of pump parts, drill bits, and pipe connections, excessive sand may also result in the deposition of a thick filter cake on the walls of the hole, or it may settle in the hole around the tools when circulation is temporarily halted, interfering with the operation of drilling tools of settling casing. The sand content test for set is used in the test for sand content determination using Bariod sand content set.
The document discusses various borehole problems that can be encountered during drilling operations, including:
- Pipe sticking caused by differential pressure or mechanical forces
- Lost circulation occurring when fluid flows into porous or fractured formations
- Hole deviation due to factors like formation heterogeneity, drilling equipment, and drilling parameters
- Pipe failures from twistoff, parting, collapse, burst, or fatigue
- Borehole instability issues like hole closure, enlargement, fracturing or collapse
- Mud contamination from solids, salts, or formation fluids entering the drilling fluid system
- Formation damage near the wellbore from plugging by solids or fluid invasion impairing permeability
Proper planning, monitoring, and application of best
Grouting and guniting are construction techniques used to fill voids and apply concrete coatings. Grouting involves placing a cementitious mixture into cavities to strengthen structures, fill gaps, and stop leaks. There are different types of grouts for various applications. The guniting process involves mixing cement and sand then projecting it at high pressure onto surfaces using compressed air. It can be used on vertical, overhead and horizontal surfaces to rehabilitate concrete structures. Both grouting and guniting are effective techniques for repairing and strengthening buildings and infrastructure.
1) A drilling operator encountered pressure spikes of up to 1.2 ppg higher than expected ECD when using a clay-based mud, leading to lost circulation and wellbore collapse.
2) On a subsequent well, the operator used a clay-free synthetic mud, which eliminated pressure spikes even when rapidly bringing pumps online, keeping ECDs low and avoiding losses.
3) The clay-free mud forms fragile gels that break easily with applied shear, transitioning smoothly from static to circulating conditions without overpressuring the formation, unlike progressive gels from clay-based muds which require more pressure to resume flow.
Once a well is drilled and cased, completion engineers optimize production by inserting equipment into the wellbore. Completion involves perforating the casing near productive formations, installing tubing and other equipment like packers and valves, and performing operations like fracturing or sand control to facilitate hydrocarbon flow. The goal is to recover the maximum amount of oil and gas possible at a reasonable cost. Engineers consider formation evaluation data, expected production rates and conditions, and may install equipment like pumps or gas lift systems as needed to optimize each individual well completion.
Field Lubricity Measurements Correlate with Improved Performance of Novel Wat...jerianasmith
A significant function of drilling fluids is reduction of frictional forces between the wellbore and the drill string. New techniques in drilling and completions are being used to drill horizontal wells in unconventional resources.
Drilling fluids, also called drilling muds, are circulated during rotary drilling operations to perform critical functions such as cooling the drill bit, removing drill cuttings from the wellbore, maintaining well pressure, and providing information to geologists. The key types of drilling fluids are water-based mud, oil-based mud, and air/foam. Drilling fluid properties like density, viscosity, gel strength, and filtration must be carefully controlled to prevent problems during drilling like blowouts, stuck pipe, and hole instability.
This is an academic lecture for Diploma in Engineering 7th Semester Mining and Mine Survey Technology. The Course related to this presentation is Cementing.
The fifth presentation of a series of presentations on Operations Geology. Very basic, just to introduce beginners to operations geology. I hope the end users will find this and the following presentations very helpful.
special concrete and high performance concreteErankajKumar
GROUTING OF CONCRETE, advantage ofGrouting,Characteristics of Grouting, GUNTING OF
CONCRETE, Application of Guniting, Properties of Guniting, advantage and disadvantage of Guniting, UNDERWATER CONCRETING, Properties of underwater concrete, METHODS OF UNDERWATER CONCRETE, advantage and disadvantage of underwater concrete, HOT WEATHERING CONCRETE, precautions, COLD WEATHER CONCRETING, PUMPABLE CONCRETE, Requirements of Mix Design for Pumpable Concrete, Ready Mixed Concrete RMC, Types of Ready Mixed Concrete, advantage and disadvantage of ready mixed concrete, introduction in High performance concrete HPC, selection of materials, behaviour of fresh high performance concrete HPC , behaviour of Hardened High performance concrete HPC when to use High performance concrete HPC , application of HPC , Advantage of HPC , Limitations of HPC
1. Hydraulic Fracturing and It’s Process 2
What is hydraulic fracturing? 2
Hydraulic Fracturing Process 3
2. Importance and Application of Hydraulic Fracturing in Shale Formation 4
Importance of Hydraulic Fracturing 4
Hydraulic Fracturing in Shale Formation 5
3. Inflow Performance Relationship (IPR) 6
1. What is IPR and uses of IPR? 6
2. List three main factors affecting IPR? 7
3. Explain inflow and outflow performance? 7
4. Artificial Lift Method and Its Application 8
Application of Artificial Lift 8
Hydraulic pumps 9
Beam pumps 10
5. Electric Submersible Pumps 12
6. Gas Lift Method 13
This document discusses fluid loss additive in water based mud. It begins with an introduction that describes the functions and importance of drilling fluids. It then discusses the preparation and extraction of cellulose from rich gourd loofah as a potential fluid loss additive. The document presents the results of formulating different mud samples with varying concentrations of rich gourd cellulose and compares them to a standard mud containing polyanionic cellulose. It found that rich gourd cellulose performed better at reducing fluid loss and improving rheological properties compared to the standard.
This document discusses cementing in oil and gas wells. It covers factors that affect cement slurry design like well depth and temperature. It describes cement additives that can control setting time. Float equipment like float collars and shoes are used to guide casing and enable cement circulation. Primary cementing involves pumping cement between casing and borehole to isolate formations. Secondary cementing through squeeze cementing can repair isolation barriers. Liner cementing cases off the open hole below an existing casing string. Cement plugs placed in casing are used for abandoning wells or zonal isolation.
Anup Kumar Gupta
SRF at Departmetn of Environmental Science and Engineering,Indian School of Mines, Dhanbad, India
Mine fill is an integral part of mining, different techniques have been used for the same. This presentation is focused on few of the important technique with a descriptive analysis.
Characterization of Self-compacting Concrete using Viscosity Modifying Admixt...IRJET Journal
This document summarizes research on characterizing self-compacting concrete (SCC) using viscosity modifying admixtures (VMAs). It discusses how VMAs change the cohesion of SCC without affecting fluidity, making it less sensitive to small variations. The document outlines various tests used to evaluate the rheological and hardened properties of SCC, including slump flow, V-funnel, and L-box tests. It provides details on procedures, equipment, and interpretations for each test. The goal of the research is to improve the qualities and stability of SCC through optimizing VMA content and rheological properties.
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Batteries -Introduction – Types of Batteries – discharging and charging of battery - characteristics of battery –battery rating- various tests on battery- – Primary battery: silver button cell- Secondary battery :Ni-Cd battery-modern battery: lithium ion battery-maintenance of batteries-choices of batteries for electric vehicle applications.
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Understanding Inductive Bias in Machine LearningSUTEJAS
This presentation explores the concept of inductive bias in machine learning. It explains how algorithms come with built-in assumptions and preferences that guide the learning process. You'll learn about the different types of inductive bias and how they can impact the performance and generalizability of machine learning models.
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ACEP Magazine edition 4th launched on 05.06.2024Rahul
This document provides information about the third edition of the magazine "Sthapatya" published by the Association of Civil Engineers (Practicing) Aurangabad. It includes messages from current and past presidents of ACEP, memories and photos from past ACEP events, information on life time achievement awards given by ACEP, and a technical article on concrete maintenance, repairs and strengthening. The document highlights activities of ACEP and provides a technical educational article for members.
Literature Review Basics and Understanding Reference Management.pptxDr Ramhari Poudyal
Three-day training on academic research focuses on analytical tools at United Technical College, supported by the University Grant Commission, Nepal. 24-26 May 2024
1. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
Drilling Engineering – PE 311
Chapter 2: Drilling Fluids
Introduction to Drilling Fluids
2. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
The principal functions of the drilling fluid are
1. Subsurface pressure control
2. Cuttings removal and transport
3. Suspension of solid particles
4. Sealing of permeable formations
5. Stabilizing the wellbore
6. Preventing formation damage
7. Cooling and lubricating the bit and drill string
8.Transmitting hydraulic horsepower to the bit
9.Facilitating the collection of formation data
10. Partial support of drill string and casing weights
11. Controlling corrosion
12. Assisting in cementing and completion
Principal Functions of Drilling Fluids
3. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
A column of drilling fluid exerts a hydrostatic pressure that, in field units, is equal to
P = 0.052 x ρ x TVD
where
P - hydrostatic pressure of fluid column in wellbore, psi;
ρ - mud weight in pounds per gallon (ppg)
TVD - True Vertical Depth, ft - during normal drilling operations, this corresponds to
the height of the fluid column in the wellbore.
Principal Functions of Drilling Fluids
Subsurface pressure control
4. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
Circulation of the drilling fluid causes cuttings to rise from the bottom of the hole to
the surface. Efficient cuttings removal requires circulating rates that are sufficient to
override the force of gravity acting upon the cuttings. Other factors affecting the
cuttings removal include drilling fluid density and rheology, annular velocity, hole
angle, and cuttings-slip velocity.
In most cases, the rig hydraulics program provides for an annular velocity sufficient
to result in a net upward movement of the cuttings. Annular velocity is determined by
the cross-sectional area of the annulus and the pump output.
Principal Functions of Drilling Fluids
Cuttings Removal and Transport
5. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
When the rig's mud pumps are shut down and circulation is halted (e.g., during
connections, trips or downtime), cuttings that have not been removed from the hole
must be held in suspension. Otherwise, they will fall to the bottom (or, in highly
deviated wells, to the low side) of the hole. The rate of fall of a particle through a
column of drilling fluid depends on the density of the particle and the fluid, the size of
the particle, the viscosity of the fluid, and the thixotropic (gel-strength) properties of
the fluid. The controlled gelling of the fluid prevents the solid particles from settling,
or at least reduces their rate of fall. High gel strengths also require higher pump
pressure to break circulation. In some cases, it may be necessary to circulate for
several hours before a trip in order to clean the hole of cuttings and to prevent fill in
the bottom of the hole from occurring during a round trip.
Principal Functions of Drilling Fluids
Suspension of Solid Particles
6. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
As the drill bit penetrates a permeable formation, the liquid portion of the drilling fluid
filters into the formation and the solids form a relatively impermeable "cake" on the
borehole wall. The quality of this filter cake governs the rate of filtrate loss to the
formation. Drilling fluid systems should be designed to deposit a thin, low
permeability filter cake on the formation to limit the invasion of mud filtrate. This
improves wellbore stability and prevents a number of drilling and production
problems. Potential problems related to thick filter cake and excessive filtration
include “tight” hole conditions, poor log quality, increased torque and drag, stuck
pipe, lost circulation and formation damage.
Bentonite is the best base material from which to build a tough, low-permeability
filter cake. Polymers are also used for this purpose.
Principal Functions of Drilling Fluids
Sealing of permeable formation
7. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
The borehole walls are normally competent immediately after the bit penetrates a
section. Wellbore stability is a complex balance of mechanical and chemical factors.
The chemical composition and mud properties must combine to provide a stable
wellbore until casing can be run and cemented. Regardless of the chemical
composition of the fluid and other factors, the weight of the mud must be within the
necessary range to balance the mechanical forces acting on the wellbore. The other
cause of borehole instability is a chemical reaction between the drilling fluid and the
formations drilled. In most cases, this instability is a result of water absorption by the
shale. Inhibitive fluids (calcium, sodium, potassium, and oil-base fluids) aid in
preventing formation swelling, but even more important is the placement of a quality
filter cake on the walls to keep fluid invasion to a minimum.
Principal Functions of Drilling Fluids
Stabilizing the Wellbore
8. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
Any reduction in a producing formation’s natural porosity or permeability is
considered to be formation damage. If a large volume of drilling-fluid filtrate invades
a formation, it may damage the formation and hinder hydrocarbon production.
There are several factors to consider when selecting a drilling fluid:
• Fluid compatibility with the producing reservoir
• Presence of hydratable or swelling formation clays
• Fractured formations
• The possible reduction of permeability by invasion of nonacid soluble materials
into the formation
Principal Functions of Drilling Fluids
Preventing Formation Damage
9. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
Friction at the bit, and between the drillstring and wellbore, generates a considerable
amount of heat. The circulating drilling fluid transports the heat away from these
frictional sites by absorbing it into the liquid phase of the fluid and carrying it away.
The laying down of a thin wall of "mud cake" on the wellbore aids in reducing torque
and drag. The amount of lubrication provided by a drilling fluid varies widely and
depends on the type and quantity of drill solids and weight material, and also on the
chemical composition of the system as expressed in terms of pH, salinity and
hardness. Indications of poor lubrication are high torque and drag, abnormal wear,
and heat checking of drillstring components.
Principal Functions of Drilling Fluids
Cooling and Lubricating the Bit
10. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
During circulation, the rate of fluid flow should be regulated so that the mud pumps
deliver the optimal amount of hydraulic energy to clean the hole ahead of the bit.
Hydraulic energy also provides power for mud motors to rotate the bit and for
Measurement While Drilling (MWD) and Logging While Drilling (LWD) tools.
Hydraulics programs are based on sizing the bit nozzles to maximize the hydraulic
horsepower or impact force imparted to the bottom of the well.
Principal Functions of Drilling Fluids
Transmitting Hydraulic Horsepower to the Bit
11. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
The drilling fluid program and formation evaluation program are closely related. As
drilling proceeds, for example, mud loggers monitor mud returns and drilled cuttings
for signs of oil and gas. They examine the cuttings for mineral composition,
paleontology and visual signs of hydrocarbons. This information is recorded on a
mud log that shows lithology, penetration rate, gas detection and oil-stained
cuttings, plus other important geological and drilling parameters. Measurement-
While-Drilling (MWD) and Logging-While-Drilling (LWD) procedures are likewise
influenced by the mud program, as is the selection of wireline logging tools for post-
drilling evaluation.
Principal Functions of Drilling Fluids
Facilitating the Collection of Formation Data
12. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
With average well depths increasing, the weight supported by the surface wellhead
equipment is becoming an increasingly crucial factor in drilling. Both drillpipe and
casing are buoyed by a force equal to the weight of the drilling fluid that they
displace. When the drilling fluid density is increased, the total weight supported by
the surface equipment is reduced considerably.
Principal Functions of Drilling Fluids
Partial support of Drill String and Casing Weights
13. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
The drilling fluid must produce a wellbore into which casing can be run and
cemented effectively, and which does not impede completion operations. During
casing runs, the mud must remain fluid and minimize pressure surges so that
fracture-induced lost circulation does not occur. The mud should have a thin, slick
filter cake. To cement casing properly, the mud must be completely displaced by the
spacers, flushes and cement. Effective mud displacement requires that the hole be
near-gauge and that the mud have low viscosity and low, non-progressive gel
strengths. Completion operations such as perforating and gravel packing also
require a near-gauge wellbore and may be affected by mud characteristics
Principal Functions of Drilling Fluids
Assistance in Cementing and Completion
14. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
Various materials may be added at the surface to change or modify the characteristics of the
mud. For example:
1.Weighting agents (usually barite) are added to increase the density of the mud, which helps to
control subsurface pressures and build the wallcake.
2.Viscosifying agents (clays, polymers, and emulsified liquids) are added to thicken the mud
and increase its hole-cleaning ability.
3.Dispersants or deflocculants may be added to thin the mud, which helps to reduce surge,
swab, and circulating-pressure problems.
Mud Ingredients
15. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
4. Clays, polymers, starches, dispersants, and asphaltic materials may be added to reduce
filtration of the mud through the borehole wall. This reduces formation damage, differential
sticking, and problems in log interpretation.
5. Salts are sometimes added to protect downhole formations or to protect the mud against
future contamination, as well as to increase density.
6. Other mud additives may include lubricants, corrosion inhibitors, chemicals that tie up
calcium ions, and flocculants to aid in the removal of cuttings at the surface.
7. Caustic soda is often added to increase the pH of the mud, which improves the
performance of dispersants and reduces corrosion.
8. Preservatives, bactericides, emulsifiers, and temperature extenders may all be added to
make other additives work better.
Mud Ingredients
16. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
A water-base fluid is one that uses water for the liquid phase and commercial clays
for viscosity. The continuous phase may be fresh water, brackish water, seawater,
or concentrated brines containing any soluble salt. The commercial clays used may
be bentonite, attapulgite, sepiolite, or polymer. The use of other components such
as thinners, filtration-control additives, lubricants, or inhibiting salts in formulating a
particular drilling fluid is determined by the type of system required to drill the
formations safely and economically. Some of the major systems include fresh-water
fluids, brackish or seawater fluids, saturated salt fluids, inhibited fluids, gyp fluids,
lime fluids, potassium fluids, polymer-based fluids, and brines used in drilling,
completion or workover operations (including single-salt, potassium chloride, sodium
chloride, calcium chloride, and two and three-salt brines).
Drilling Fluid Classifications
Water-Based Drilling Fluids
17. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
In many areas, diesels were used to formulate and maintain OBMs. Crude oils had
sometimes been used instead of diesel but posed tougher safety problems. Thus,
today, mineral oils and new synthetic fluids replace diesel and crude due to their
lower toxicity.
Advantages of OBMs:
1. Shale stability: OBMs are most suited for drilling water sensitive shales. The
whole mud results non reactive towards shales.
2. ROP: allowing to drill faster than WBMs, still providing excellent shale stability
3. High Temperature: can drill where bottom hole temperature exceeds WBMs
tolerances; can handle up to 550 0
F.
Drilling Fluid Classifications
Oil-Based Drilling Fluids
18. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
4. Lubricity: OBMs has a thin filter cake and the friction between the pipe and the
wellbore is minimized, thus reducing the risk of differential sticking.
5. Low pore pressure formation: Mud weight of OBMs can be maintained less than
that of water (as low as 7.5 PPG)
6. Corrosion control: corrosion of pipe is controlled Since oil is the external phase.
7. Re-use: OBMs are well-suited to be used over and over again. They can be
stored for long periods of time since bacterial growth is suppressed.
Drilling Fluid Classifications
Oil-Based Drilling Fluids
19. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
An oil-base drilling fluid is one in which the continuous phase is oil. The terms oil-
base mud and inverted or invert-emulsion mud sometimes are used to distinguish
among the different types of oil-base drilling fluids. Traditionally, an oil-base mud is
a fluid with 0 to 5% by volume of water, while an invert-emulsion mud contains more
than 5% by volume of water. However, since most oil muds contain some emulsified
water, have oil as the liquid phase, and (if properly formulated) have an oil filtrate,
we do not distinguish among them in this discussion. Synthetic muds may include
esters, olefins, and paraffin.
Drilling Fluid Classifications
Oil-Based Drilling Fluids
20. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
Air drilling is used primarily in hard-rock areas, and in special cases to prevent
formation damage while drilling into production zones or to circumvent severe lost-
circulation problems. Air drilling includes dry air drilling, mist or foam drilling, and
aerated-mud drilling. In dry air drilling, dry air or gas is injected into the standpipe at
a volume and rate sufficient to achieve the annular velocities needed to clean the
hole of cuttings. Mist drilling is used when water or oil sands are encountered that
produce more fluid than can be dried up using dry air drilling. A mixture of foaming
agent and water is injected into the air stream, producing a foam that separates the
cuttings and helps remove fluid from the hole. In aerated mud drilling, both mud and
air are pumped into the standpipe at the same time. Aerated muds are used when it
is impossible to drill with air alone because of water sands and/or lost-circulation
situations.
Drilling Fluid Classifications
Pneumatic Fluids (Air, Gas, Mist, Foams, Gasified Muds)
22. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
The physical properties of a drilling fluid, particularly its density and rheological
properties, are monitored to assist in optimizing the drilling process. These physical
properties contribute to several important aspects of successful drilling, including:
• Providing pressure control to prevent an influx of formation fluid
• Providing energy at the bit to maximize Rate of Penetration (ROP)
• Providing wellbore stability through pressured or mechanically stressed zones
• Suspending cuttings and weight material during static periods
• Permitting separation of drilled solids and gas at surface
• Removing cuttings from the well
Drilling Fluid Properties
23. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
The concepts of shear rate and shear stress apply to all fluid flow, and can be
describe in term of two fluid layers (A and B) moving past each other when a force
(F) has been applied.
Drilling Fluid Properties
Viscosity
24. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
When a fluid is flowing, a force exists in the fluid that opposes the flow. This force is
known as the shear stress. It can be thought of as a frictional force that arises
when one layer of fluid slides by another. Since it is easier for shear to occur
between layers of fluid than between the outer most layer of fluid and the wall of a
pipe, the fluid in contact with the wall does not flow. The rate at which one layer is
moving past the next layer is the shear rate. The shear rate is therefore a velocity
gradient. The formula for the shear rate is
Drilling Fluid Properties
Viscosity
25. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
In the most general sense, viscosity describes a substance’s resistance to flow.
Hence a high-viscosity drilling mud may be characterized as "thick," while a low-
viscosity mud may be described as "thin."
Viscosity (µ), by definition, is the ratio of shear stress (τ) to shear rate (γ):
Unit: PaS, NS/m2
, kg/ms, cp, dyneS/cm2
, lbfS/100ft2
Drilling Fluid Properties
Viscosity
26. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
The simplest class of fluids is called Newtonian. The base fluids (freshwater,
seawater, diesel oil, mineral oils and synthetics) of most drilling fluids are
Newtonian. In these fluids, the shear stress is directly proportional to the shear rate.
The points lie on a straight line passing through the origin (0,0) of the graph on
rectangular coordinates. The viscosity of a Newtonian fluid is the slope of this shear
stress/shear rate line. The yield stress (stress required to initiate flow) of a
Newtonian fluid will always be zero. When the shear rate is doubled, the shear
stress is also doubled. When the circulation rate for this fluid is doubled, the
pressure required to pump the fluid will be squared (e.g. 2 times the circulation rate
requires 4 times the pressure).
Fluid Types
Newtonian Fluids
27. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
The shear stress at various shear rates
must be measured in order to
characterize the flow properties of a
fluid. Only one measurement is
necessary since the shear stress is
directly proportional to the shear rate
for a Newtonian fluid. From this
measurement the shear stress at any
other shear rate can be calculated from
the equation:
Fluid Types
Newtonian Fluids
28. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
When a fluid contains clays or colloidal particles, these particles tend to “bump” into
one another, increasing the shear stress or force necessary to maintain a given flow
rate. If these particles are long compared to their thickness, the particle interference
will be large when they are randomly oriented in the flow stream. However, as the
shear rate is increased, the particles will “line up” in the flow stream and the effect of
particle interaction is decreased. This causes the velocity profile in a pipe to be
different from that of water. In the center of the pipe, where the shear rate is low, the
particle interference is high and the fluid tends to flow more like a solid mass. The
velocity profile is flattened. This flattening of the velocity profile increases the sweep
efficiency of a fluid in displacing another fluid and also increases the ability of a fluid
to carry larger particles.
Fluid Types
Non-Newtonian Fluids
29. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
A rheological model is a description of the relationship between the shear stress
and shear rate. Newton’s law of viscosity is the rheological model describing the
flow behavior of Newtonian fluids. It is also called the Newtonian model. However,
since most drilling fluids are non-Newtonian fluids, this model does not describe
their flow behavior. In fact, since no single rheological model can precisely describe
the flow characteristics of all drilling fluids, many models have been developed to
describe the flow behavior of non-Newtonian fluids. Bingham Plastic, Power Law
and Modified Power Law models are discussed. The use of these models requires
measurements of shear stress at two or more shear rates. From these
measurements, the shear stress at any other shear rate can be calculated.
Fluid Types
Non-Newtonian Fluids
30. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
Fluid Types
Rotational Viscometer
31. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
The Bingham Plastic model has been used most often to describe the flow
characteristics of drilling fluids. It is one of the older rheological models currently in
use. This model describes a fluid in which a finite force is required to initiate flow
(yield point) and which then exhibits a constant viscosity with increasing shear rate
(plastic viscosity).
Fluid Types
Bingham Plastic Fluids
32. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
The two-speed viscometer was designed to measure the Bingham Plastic
rheological values for yield point and plastic viscosity. A flow curve for a typical
drilling fluid taken on the two-speed Fann VG meter is illustrated in Figure below.
The slope of the straight line portion of this consistency curve is plastic viscosity.
Fluid Types
Bingham Plastic Fluids
33. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
Most drilling fluids are not true Bingham Plastic fluids. For the typical mud, if a
consistency curve for a drilling fluid is made with rotational viscometer data, a non-
linear curve is formed that does not pass through the origin, as shown in Flow
diagram of Newtonian and typical mud. The development of gel strengths causes
the y-intercept to occur at a point above the origin due to the minimum force
required to break gels and start flow. Plug flow, a condition wherein a gelled fluid
flows as a “plug” with a flat viscosity profile, is initiated as this force is increased. As
the shear rate increases, there is a transition from plug to viscous flow. In the
viscous flow region, equal increments of shear rate will produce equal increments of
shear stress, and the system assumes the flow pattern of a Newtonian fluid.
Fluid Types
Bingham Plastic Fluids
34. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
Fluid Types
Bingham Plastic Fluids
35. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
The Power Law model attempts to solve the shortcomings of the Bingham Plastic
model at low shear rates. The Power Law model is more complicated than the
Bingham Plastic model in that it does not assume a linear relationship between
shear stress and shear rate. However, like Newtonian fluids, the plots of shear
stress vs. shear rate for Power Law fluids go through the origin.
Fluid Types
Power Law Model
36. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
This model describes a fluid in which the shear stress increases as a function of the
shear rate mathematically raised to some power. Mathematically, the Power Law
model is expressed as
τ = Kγn
Where:
τ = Shear stress
K = Consistency index
γ = Shear rate
n = Power Law index
Fluid Types
Power Law Model
37. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
Plotted on a log-log graph, a Power Law fluid shear stress/shear rate relationship
forms a straight line in the log-log plot. The “slope” of this line is “n” and “K’ is the
intercept of this line. The Power Law index “n” indicates a fluid’s degree of non-
Newtonian behavior over a given shear rate range.
Fluid Types
Power Law Model
38. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
n = Power Law index or exponent
K = Power Law consistency index or fluid index (dyne sec–n/cm2)
θ1 = Mud viscometer reading at lower shear rate
θ2 = Mud viscometer reading at higher shear rate
ω1 = Mud viscometer RPM at lower shear rate
ω2 = Mud viscometer RPM at higher shear rate
Fluid Types
Power Law Model
39. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
A rotational viscometer containing a non-Newtonaian fluid gives a dial reading of 12
at a rotor speed of 300 rpm and a dial reading of 20 at a rotor speed of 600 rpm.
Determine the rheological model of this fluid in two cases: Bingham model and
Power Law model
Fluid Types
Example
40. Drilling Engineering – Fall 2012
Prepared by: Tan Nguyen
A rotational viscometer containing a non-Newtonaian fluid gives a dial reading of 12
at a rotor speed of 300 rpm and a dial reading of 20 at a rotor speed of 600 rpm.
Determine the rheological model of this fluid in two cases: Bingham model and
Power Law model:
Bingham model:
Power Law model:
Fluid Types
Example